On the subject of dangerous oils I contacted Sara from Wren some time ago (I use a Wren turbine). I have had health problems in the past & am keen to prevent any new ones! I hope Sara does not mind me quoting her.

When asked about Mobil DTE light:

Hello John,

I think the Mobil DTE light was recommended by one of our customers, Phil from Hobbyparts, who has been using it. Wren have been using Castrol TTS synthetic motorcycle oil for over a year, and have started to recommend this to our customers. We used to use marine engine oil (TCW3) but this is slightly sticky, to coat marine engines against salt corrosion, so we have moved to a less sticky oil.

and further:

I've just seen the thread on RCU about oil and realised that the Mobil DTE light is the GTBA's James Hill's recommendation - Tom Wilkinson will have got that from James, not us. It should be OK though - but we haven't used it.

Castrol TTS is available in Oz from Supercheap Auto, there's a store 5 minutes away from my house so it's a no brainer. - John.